1. Field of the Invention
The present invention is related to an apparatus and its method that are used to detect a burst noise and then reduce the interference of the burst noise by controlling an operation of an adaptive apparatus, such as an equalizer, so as to improve the robustness of the adaptive apparatus.
2. Description of Related Art
In general, a high-frequency radio signal receiving apparatus needs to be essentially immune to the influence of noise such as impulsive noise or burst noise. The burst noise and impulsive noise damage the normal operation of a receiver, especially the device with memory and feedback such as an equalizer and a Viterbi decoder. Once the state machines of these devices are triggered to an improper state, it usually requires a lot of time to recover the original state.
Reference is made to FIG. 16, which shows a block diagram of a conventional adaptive apparatus for equalizing the channel for signal transmission. As shown in this figure, the apparatus includes an equalizer 160, a decision circuit 162 and an error estimator 164. Therein, the equalizer 160 further has an output generating unit 1601 and multiple coefficient storage/updating circuits 1602. First, the signals received externally are inputted to the equalizer 160 and processed according to the coefficients of the equalizer 160 set previously. Then, the processed signals are sent to the decision circuit 162 for data recovery. After that, the recovered data is passed to the error estimator 164. The error estimator 164 is used to check the data received from the decision circuit 162 and update the coefficients of the equalizer according to the status of the received data. However, the conventional adaptive apparatus can only be used to equalize the long-term states of the occupied channel. Once an unexpected noise occurs, such as a burst noise, the apparatus will be influenced severely and require a lot of time to recover the original state.